LOWER TRANSITION ROCKS. II3 



some five miles to the south-east by south. The base of the wedge 

 measures about 3 miles across. 



The inversion of the upper beds of the eastern side of the syn- 

 clinal, though less conspicuous than to the north of the Bhima- 

 gandi gorge, can be seen for some distance south of the Narihalla 

 valley on the west flank of the Donimale, and again in the hills to 

 the south-south-east of the apex. 



To the south of the apex the strata composing the east side of the 

 Thinning out of the synclinal very generally commence to thin out, 

 formations generally. and an area of progressively diminishing sedi- 



mentation is entered upon and is found to extend to the southernmost 

 end of the synclinal, where the strata have dwindled away to mere 

 films which lie around the rugosities of the old gneissic surface. The 

 thinning out of the beds is very remarkable here, and can be far better 

 realised here than at the northern extremity of the synclinal. 



The general surface of the Donimale plateau is fairly level, but a 

 few trifling ridges rise out of it here and there, formed by the outcrops 

 of haematitic beds which project slightly over the surface and are 

 generally covered with thick scrubby jungle. The general surface is 

 but thinly wooded, but per contra it is mostly densely covered with 

 long grass, which is not at all easy to traverse, and completely conceals 

 the ground between the low outcrops just named. 1 



1 Everybody that has crossed spreads of dry grass in the hot weather knows how 

 extremely slippery it makes one's boot soles. I never realised this more than 

 when pushing my way across the trackless grass spread on the Donimale. The growth 

 was much too thick and high to let the ground be seen, and where uneven ground or 

 loose stones were hidden under the grass, stumbles were incessant and sprawls not in- 

 frequent. My native companions fared almost as badly as I did despite their bare feet. 

 Down among the long grass one got into a much hotter atmosphere so full of dust as to 

 be perfectly suffocating and to cause violent fits of sneezing, as in hay fever. A little 

 dog that followed me through those 5 miles of long grass suffered greatly from the 

 hot dusty air and became quite ill from it. 



The dust seemed to be purely vegetable in its nature and was doubtless formed by 

 the breaking up of the crisp dead grasses and leaves under action of brisk winds. The 

 presence of such dust cannot fail to give rise to an explosive and immensely more rapid 

 spread of fire when the grass has been ignited than if the dust did not exist among it. 

 That the presence of dry coal dust in large quantities in the passages of collieries im- 

 mensely intensifies the destructive action of explosions is a well ascertained fact and the 

 action of the dry grass dust may well be analogous. 



H ( 1*3 ) 



